|  |  |  | | | | | TE-RegenMed-StemCell feed | | | | | | | | | | | | | | | | | | | Effect of Reishi polysaccharides on human stem/progenitor cells. Bioorg Med Chem. 2010 Nov 3; Authors: Chen WY, Yang WB, Wong CH, Shih DT The polysaccharide fraction of Ganoderma lucidum (F3) was found to benefit our health in many ways by influencing the activity of tissue stem/progenitor cells. In this study, F3 was found to promote the adipose tissue MSCs' aggregation and chondrosphere formation, with the increase of CAM (N-CAM, I-CAM) expressions and autokine (BMP-2, IL-11, and aggrecan) secretions, in an in vitro chondrogenesis assay. In a stem cell expansion culture, it possesses the thrombopoietin (TPO) and GM-CSF like functions to enhance the survival/renewal abilities of primitive hematopoietic stem/progenitor cells (HSCs). F3 was found to promote the dendrite growth of blood mononuclear cells (MNCs) and the expression of cell adhesion molecules in the formation of immature dendritic cells (DC). On the other hand, F3 exhibited inhibitory effects on blood endothelial progenitor (EPC) colony formation, with concomitant reduction of cell surface endoglin (CD105) and vascular endothelial growth factor receptor-3 (VEGFR-3) marker expressions, in the presence of angiogenic factors. A further cytokine array analysis revealed that F3 indeed inhibited the angiogenin synthesis and enhanced IL-1, MCP-1, MIP-1, RANTES, and GRO productions in the blood EPC derivation culture. Collectively, we have demonstrated that the polysaccharide fraction of G. lucidum F3 exhibits cytokine and chemokine like functions which are beneficial to human tissue stem/progenitor cells by modulating their CAM expressions and biological activities. These findings provide us a better the observation that F3 glycopolysaccharides indeed possesses anti-angiogenic and immune-modulating functions and promotes hematopoietic stem/progenitor cell homing for better human tissue protection, reducing disease progression and health. PMID: 21055951 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | [Effects of in vitro cultured adipose-derived stem cells of rats on the tympanic membrane fibroblasts.] Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi. 2010 Jul;45(7):587-591 Authors: Lei F, Sun JJ, Liu Y, Jiang DQ OBJECTIVE: To explore the effects of rats adipose-derived stem cell (ASC) on the proliferation and migration of fibroblasts from the tympanic membrane, and to discuss the possibility and significance of therapy with ASC for tympanic membrane (TM) healing and regeneration. METHODS: Wistar rats were sacrificed, and then the isolation, culture and identification of both ASC and the TM fibroblasts were performed respectively. To verify the effect of ASC on fibroblasts proliferation, transwell co-culture system was used. To examine the effect of ASC on fibroblasts migration, cell migration assay with transwell was also applied. All the data were analyzed under a confocal laser scan microscopy system. RESULTS: Immunofluorescence of cell surface markers indicated that rats ASC were positive for both of CD44 and CD29, but negative for CD34. The rat TM fibroblasts were positive for vimentin. The fibroblasts co-cultured with ASC proliferated faster than the fibroblasts of control group, and the difference of the cell counting number between the two groups was significant (t = 6.75, P = 0.003). Compared with the control group, the fibroblasts cultured with ASC conditioned culture medium migrated significantly faster, and the space between the fibroblasts and the polycarbonate membrane pore was significantly shortened at different time point (1, 2.5 and 4 h, P < 0.05). The cell number of the fibroblasts that had migrated through the polycarbonate membrane had been significantly increased 5 h after migration (P < 0.05). CONCLUSION: ASC might promote TM fibroblasts proliferation and migration by paracrine activation, and it will faciliate the regeneration of TM fibrous layer. PMID: 21055060 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Co-transplantation of Mouse Neural Stem Sells (mNSCs) with Adipose Tissue-derived Mesenchymal Stem Sells Improves mNSC Survival in a Rat Spinal Cord Injury Model. Cell Transplant. 2010 Nov 5; Authors: Oh JS, Kim KN, An SS, Pennant WA, Kim HJ, Gwak SJ, Yoon DH, Lim MH, Choi BH, Ha Y The low survival rate of graft stem cells after transplantation into recipient tissue is a major obstacle for successful stem cell therapy. After transplantation into the site of spinal cord injury, the stem cells face not only hypoxia due to low oxygen conditions, but also a lack of nutrients caused by damaged tissues and poor vascular supply. To improve the survival of therapeutic stem cells after grafting into the injured spinal cord, we examined the effects of co-transplanting mouse neural stem cells (mNSCs) and adipose tissue-derived mesenchymal stem cells (AT-MSCs) on mNSC viability. The viability of mNSCs in co-culture with AT-MSCs was significantly increased compared to mNSCs alone in an in vitro injury model using serum deprivation (SD), hydrogen peroxide (H₂O₂), and combined (SD + H₂O₂) injury mimicking the ischemic environment of the injured spinal cord. We demonstrated that AT-MSCs inhibited the apoptosis of mNSCs in SD, H₂O₂, and combined injury models. Consistent with these in vitro results, mNSCs transplanted into rat spinal cords with AT-MSCs showed better survival rates than mNSCs transplanted alone. These findings suggest that co-transplantation of mNSCs with AT-MSCs may be a more effective transplantation protocol to improve the survival of cells transplanted into the injured spinal cord. PMID: 21054952 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Stem cells to treat muscular dystrophies - Where are we? Neuromuscul Disord. 2010 Nov 3; Authors: Meng J, Muntoni F, Morgan JE The muscular dystrophies are inherited disorders characterised by progressive muscle wasting and weakness. Stem cell therapy is considered to be one of the most promising strategies for treating muscular dystrophies. In this review, we first examine the evidence that a stem cell could be used to treat muscular dystrophies, and then discuss the criteria that an ideal stem cell should meet. We also highlight the importance of standard operation procedures to be followed for ensuring the consistent and reproducible efficacy of a particular stem cell. While at the moment the scientific community is looking for an ideal stem cell to treat muscular dystrophies, it is clear that in order for this field to benefit from therapeutic stem cell applications, additional careful investigations are required. PMID: 21055938 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Co-transplantation of Mouse Neural Stem Sells (mNSCs) with Adipose Tissue-derived Mesenchymal Stem Sells Improves mNSC Survival in a Rat Spinal Cord Injury Model. Cell Transplant. 2010 Nov 5; Authors: Oh JS, Kim KN, An SS, Pennant WA, Kim HJ, Gwak SJ, Yoon DH, Lim MH, Choi BH, Ha Y The low survival rate of graft stem cells after transplantation into recipient tissue is a major obstacle for successful stem cell therapy. After transplantation into the site of spinal cord injury, the stem cells face not only hypoxia due to low oxygen conditions, but also a lack of nutrients caused by damaged tissues and poor vascular supply. To improve the survival of therapeutic stem cells after grafting into the injured spinal cord, we examined the effects of co-transplanting mouse neural stem cells (mNSCs) and adipose tissue-derived mesenchymal stem cells (AT-MSCs) on mNSC viability. The viability of mNSCs in co-culture with AT-MSCs was significantly increased compared to mNSCs alone in an in vitro injury model using serum deprivation (SD), hydrogen peroxide (H₂O₂), and combined (SD + H₂O₂) injury mimicking the ischemic environment of the injured spinal cord. We demonstrated that AT-MSCs inhibited the apoptosis of mNSCs in SD, H₂O₂, and combined injury models. Consistent with these in vitro results, mNSCs transplanted into rat spinal cords with AT-MSCs showed better survival rates than mNSCs transplanted alone. These findings suggest that co-transplantation of mNSCs with AT-MSCs may be a more effective transplantation protocol to improve the survival of cells transplanted into the injured spinal cord. PMID: 21054952 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Promising cell-based therapy for bone regeneration using stem cells from deciduous teeth, dental pulp, and bone marrow. Cell Transplant. 2010 Nov 5; Authors: Yamada Y, Ito K, Nakamura S, Ueda M, Nagasaka T We attempted to regenerate bone in a significant osseous defect with various stem cells from deciduous teeth, extracted from puppies, and grafted them into a parent canine mandible as an allograft, parent dental pulp, and bone marrow by tissue engineering and regenerative medicine technology using platelet-rich plasma as an autologous scaffold and signal molecules. Initially, teeth were extracted from a child and parent hybrid canine mandible region and bone marrow (canine mesenchymal stem cells; cMSCs), and parent teeth (canine dental pulp stem cells; cDPSCs), and stem cells were extracted from deciduous teeth (puppy deciduous teeth stem cells; pDTSCs). After 4 weeks, bone defects were prepared on both sides of the mandible with a trephine bar. Graft materials were implanted into these defects: 1) control (defect only), 2) PRP, 3) cMSCs/PRP, 4) cDPSCs/PRP, and 5) pDTSCs/PRP to investigate the effect of stem cells. The newly formed bones were evaluated by histology and histomorphometric analysis in the defects at 2, 4, and 8 weeks. According to histological observations, the cMSCs/PRP, cDPSCs/PRP, and pDTSCs/PRP group had well-formed mature bone and neovascularization compared with the control (defect only) and PRP groups at 4 and 8 weeks, respectively, and the mineralized tissues in cMSCs/PRP, cDPSCs/PRP, and pDTSCs/PRP specimens were positive for osteocalcin at 8 weeks. Histometrically, newly formed bone areas were 19.0±2.9% (control), 19.7±6.0% (PRP), 52.8±3.5% (cMSCs/PRP), 61.6±1.3% (cDPSCs/PRP) and 54.7±2.2% (pDTSCs/PRP) at 8 weeks. There were significant differences between cMSCs, cDPSCs, pDTSCs/PRP, and control and PRP groups. These results demonstrate that stem cells from deciduous teeth, dental pulp, and bone marrow with PRP have the ability to form bone, and bone formation with DTSCs might have the potential to generate a graft between a child and parent. This pre-clinical study could pave the way for stem cell therapy in orthopedics and oral maxillofacial reconstruction for clinical application. PMID: 21054950 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Improved sub-cellular resolution via simultaneous analysis of organelle proteomics data across varied experimental conditions. Proteomics. 2010 Sep 30; Authors: Trotter MW, Sadowski PG, Dunkley TP, Groen AJ, Lilley KS Spatial organisation of proteins according to their function plays an important role in the specificity of their molecular interactions. Emerging proteomics methods seek to assign proteins to sub-cellular locations by partial separation of organelles and computational analysis of protein abundance distributions among partially separated fractions. Such methods permit simultaneous analysis of unpurified organelles and promise proteome-wide localisation in scenarios wherein perturbation may prompt dynamic re-distribution. Resolving organelles that display similar behavior during a protocol designed to provide partial enrichment represents a possible shortcoming. We employ the Localisation of Organelle Proteins by Isotope Tagging (LOPIT) organelle proteomics platform to demonstrate that combining information from distinct separations of the same material can improve organelle resolution and assignment of proteins to sub-cellular locations. Two previously published experiments, whose distinct gradients are alone unable to fully resolve six known protein-organelle groupings, are subjected to a rigorous analysis to assess protein-organelle association via a contemporary pattern recognition algorithm. Upon straightforward combination of single-gradient data, we observe significant improvement in protein-organelle association via both a non-linear support vector machine algorithm and partial least-squares discriminant analysis. The outcome yields suggestions for further improvements to present organelle proteomics platforms, and a robust analytical methodology via which to associate proteins with sub-cellular organelles. PMID: 21058340 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Erythropoietin and the truths of science. J Nephrol. 2010 Nov 3; Authors: Buemi M, Campo S, Cernaro V, Donato V, Lacquaniti A In recent years, the use of recombinant human erythropoietin (rHuEpo) has exploded all over the world, and thanks to this, the anemia of patients with chronic renal failure has practically been resolved with its administration. Administration of rHuEpo certainly plays a role in regenerative medicine in vitro and in vivo, because it intervenes in angiogenesis, the persistent natural regenerative activity of humans. Unfortunately, in recent randomized studies, the beneficial effects of rHuEpo have been accompanied by an unanticipated increase in mortality. Its effects are negative in presence of cancer development, but positive in other conditions, as it can protect heart tissue, brain and kidney. Now that its adverse effects have caused the US Food and Drug Administration to issue a black-box warning, it may be time to review what we know about the history and physiology of this plasma factor that appears to be more than just an erythrocyte production factor. Directions for future research hold promise, but only after we have fully understood the physiology of this potent growth factor. PMID: 21058263 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | 3D-Plotted scaffolds with controlled pore size gradients: effect of scaffold geometry on mechanical performance and cell seeding efficiency. Acta Biomater. 2010 Nov 3; Authors: Sobral JM, Caridade SG, Sousa RA, Mano JF, Reis RL Scaffolds produced by Rapid Prototyping techniques have proved their value for tissue engineering applications, due to ability to produce predetermined forms and structures featuring fully interconnected pore architectures. Nevertheless, low cell seeding efficiency and non-uniform distribution of cells still remains a major limitation when using such type of scaffolds. This can be mainly attributed to inadequate pore architecture of scaffolds produced by rapid prototyping (RP) and limited efficiency of cell seeding techniques normally adopted. In this study, we aimed at producing scaffolds with pore-size gradients to enhance cell seeding efficiency and control the spatial organization of cells within the scaffold. Scaffolds based on blends of starch with poly(ε-caprolactone) (SPCL) featuring both homogeneously spaced pores (based on pore size of 0.75 mm and 0.1 mm) and pore-size gradients (based on pore size of 0.1-0.75-0.1 mm and 0.75-0.1-0.75 mm) were designed and produced by 3D-Plotting. The mechanical performance of the scaffolds was characterized using dynamic mechanical analysis and conventional compression testing under wet conditions and subsequently characterized using Scanning Electron Microscopy (SEM) and micro-computed tomography (μ-CT). Osteoblast-like cells were seeded on such scaffolds to investigate cell seeding efficiency and the ability to control zonal distribution of cells upon seeding. Scaffolds featuring continuous pore-size gradients were originally produced. These scaffolds showed to have intermediate mechanical and morphological properties when compared with the homogenous pore-size ones. The pore-size gradient scaffolds improved seeding efficiency from ≈35% in homogenous scaffolds to ≈70% under static culturing conditions. Fluorescence images of cross sections of the scaffolds revealed that scaffolds with pore size gradients induce a more homogenous distribution of cells within the scaffold. PMID: 21056125 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Human urine-derived stem cells seeded in a modified 3D porous small intestinal submucosa scaffold for urethral tissue engineering. Biomaterials. 2010 Nov 3; Authors: Wu S, Liu Y, Bharadwaj S, Atala A, Zhang Y The goal of this study was to determine whether urothelial cells (UC) and smooth muscle cells (SMC) derived from the differentiation of urine-derived stem cells (USC) could be used to form engineered urethral tissue when seeded on a modified 3-D porous small intestinal submucosa (SIS) scaffold. Cells were obtained from 12 voided urine samples from 4 healthy individuals. USC were isolated, characterized and induced to differentiate into UC and SMC. Fresh SIS derived from pigs was decellularized with 5% peracetic acid (PAA). Differentiated UC and SMC derived from USC were seeded onto SIS scaffolds with highly porous microstructure in a layered co-culture fashion and cultured under dynamic conditions for one week. The seeded cells formed multiple uniform layers on the SIS and penetrated deeper into the porous matrix during dynamic culture. USC that were induced to differentiate also expressed UC markers (Uroplakin-III and AE1/AE3) or SMC markers (α-SM actin, desmin, and myosin) after implantation into athymic mice for one month, and the resulting tissues were similar to those formed when UC and SMC derived from native ureter were used. In conclusion, UC and SMC derived from USC could be maintained on 3-D porous SIS scaffold. The dynamic culture system promoted 3-D cell-matrix ingrowth and development of a multilayer mucosal structure similar to that of native urinary tract tissue. USC may serve as an alternative cell source in cell-based tissue engineering for urethral reconstruction or other urological tissue repair. PMID: 21055807 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | The surface molecular functionality of decellularized extracellular matrices. Biomaterials. 2010 Nov 3; Authors: Barnes CA, Brison J, Michel R, Brown BN, Castner DG, Badylak SF, Ratner BD Decellularization of tissues and organs is a successful platform technology for creating scaffolding materials for tissue engineering and regenerative medicine. It has been suggested that the success of these materials upon implantation is due to the molecular signals provided by the remaining scaffold extracellular matrix (ECM) components presented to probing cells in vivo as they repopulate the surface. For this study, decellularized matrices were created from esophagus, bladder, and small intestine harvested from adult male Fischer 344 rats. The three decellularized matrices (each originating from source tissues which included an epithelial lining on their luminal surfaces) were immunostained for collagen IV and laminin to determine basement membrane retention. Scanning electron micrographs of the surfaces were used to provide insight into the surface topography of each of the decellularized tissues. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to generate high-resolution mass spectra for the surfaces of each scaffold. This surface-sensitive technique allows for detailed molecular analysis of the outermost 1-2 nm of a material and has been applied previously to thin protein films and secreted ECM proteins on poly(N-isopropyl acrylamide) (polyNIPAAM) surfaces. To extract trends from within the complex ToF-SIMS dataset, a multivariate analysis technique, principal component analysis (PCA), was employed. Using this method, a molecular fingerprint of each surface was created and separation was seen in the PCA scores between the decellularized esophagus and the decellularized small intestine samples. The PCA scores for the decellularized bladder sample fell between the previous two decellularized samples. Protein films of common extracellular matrix constituents (collagen IV, collagen I, laminin, and Matrigel) were also investigated. The PCA results from these protein films were used to develop qualitative hypotheses for the relationship of the key fragments identified from the PCA of the decellularized ECMs. PMID: 21055805 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | [miRNA changes in the reverse remodeling heart of rats.] Zhonghua Xin Xue Guan Bing Za Zhi. 2010 Aug;38(8):745-750 Authors: Wang J, Zheng Z, Lin FQ, Sun CC, Xu RX, Hu SS OBJECTIVE: To establish a reverse remodeling heart model in rats and observe collagen and TGF-β expression and relevant microRNAs changes during reverse remodeling. METHODS: Lewis rats were divided into four groups including sham (NL, n = 10), abdominal aortic constriction (AAC, n = 10), heterotopic transplantation of abdominal aortic constriction (AAC-HT, n = 9) and heterotopic transplantation of normal heart (HT, n = 8). Left ventricular wall thickness and LV cavity were measured by echocardiography. The cardiomyocyte cross-sectional area (CSA) was determined on HE stained sections. Immunohistochemical and qRT-PCR were used to detect collagen and TGF-β expressions. miRNAs were detected by MicroRNA microarray. RESULTS: Heart weight, left ventricular wall thickness and CSA were significantly increased in AAC hearts compared to those in the NL and AAC-HT hearts. The collagen and TGF-β were increased in AAC hearts and further increased in AAC-HT hearts. miRNA microarray evidenced more than two folds changes on 82 miRNAs compared to NL (10 in AAC, 32 in AAC-HT and 40 in HT). CONCLUSION: Rat abdominal aortic constriction and heterotopic transplantation could be used as a reverse remodeling heart model and significant collagen and TGF-β as well microRNA expression changes were evidenced in this model. PMID: 21055145 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Promising cell-based therapy for bone regeneration using stem cells from deciduous teeth, dental pulp, and bone marrow. Cell Transplant. 2010 Nov 5; Authors: Yamada Y, Ito K, Nakamura S, Ueda M, Nagasaka T We attempted to regenerate bone in a significant osseous defect with various stem cells from deciduous teeth, extracted from puppies, and grafted them into a parent canine mandible as an allograft, parent dental pulp, and bone marrow by tissue engineering and regenerative medicine technology using platelet-rich plasma as an autologous scaffold and signal molecules. Initially, teeth were extracted from a child and parent hybrid canine mandible region and bone marrow (canine mesenchymal stem cells; cMSCs), and parent teeth (canine dental pulp stem cells; cDPSCs), and stem cells were extracted from deciduous teeth (puppy deciduous teeth stem cells; pDTSCs). After 4 weeks, bone defects were prepared on both sides of the mandible with a trephine bar. Graft materials were implanted into these defects: 1) control (defect only), 2) PRP, 3) cMSCs/PRP, 4) cDPSCs/PRP, and 5) pDTSCs/PRP to investigate the effect of stem cells. The newly formed bones were evaluated by histology and histomorphometric analysis in the defects at 2, 4, and 8 weeks. According to histological observations, the cMSCs/PRP, cDPSCs/PRP, and pDTSCs/PRP group had well-formed mature bone and neovascularization compared with the control (defect only) and PRP groups at 4 and 8 weeks, respectively, and the mineralized tissues in cMSCs/PRP, cDPSCs/PRP, and pDTSCs/PRP specimens were positive for osteocalcin at 8 weeks. Histometrically, newly formed bone areas were 19.0±2.9% (control), 19.7±6.0% (PRP), 52.8±3.5% (cMSCs/PRP), 61.6±1.3% (cDPSCs/PRP) and 54.7±2.2% (pDTSCs/PRP) at 8 weeks. There were significant differences between cMSCs, cDPSCs, pDTSCs/PRP, and control and PRP groups. These results demonstrate that stem cells from deciduous teeth, dental pulp, and bone marrow with PRP have the ability to form bone, and bone formation with DTSCs might have the potential to generate a graft between a child and parent. This pre-clinical study could pave the way for stem cell therapy in orthopedics and oral maxillofacial reconstruction for clinical application. PMID: 21054950 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Novel cell culture model using pure hydrostatic pressure and a semipermeable membrane pouch. Cell Transplant. 2010 Nov 5; Authors: Mizuno S Cell constructs and culture methods are essential tools in tissue engineering. The cell construct should be equivalent to the native cartilage it is intended to replace. Thus, three-dimensional cell constructs are usually composed of a high density of cells and dense extracellular matrix. However, dense constructs suffer from a lack of passive nutrient supply, gas exchange, and removal of degraded debris. We have developed a novel hydrostatic pressure/perfusion culture system that improves the quality of neo-tissues, providing an automated and affordable system for clinical applications. We have also developed a semipermeable membrane pouch that contains a fragile amorphous cell carrier. Although amorphous material is difficult to handle, it is a useful medium in which to deliver cells to the desired site via injection. We evaluated phenotypes of bovine articular chondrocytes embedded in a collagen type I gel enclosed within membrane pouches permeable to molecules of various sizes. Constant or cyclic hydrostatic pressure was externally applied to the medium phase with a new culture system. Accumulation of cartilage specific matrix was promoted with a 500-kD cutoff membrane pouch and cyclic hydrostatic pressure at 0.5 MPa, 0.5 Hz. This new method will be useful in the delivery of engineered cells to a desired tissue in regenerative medicine. PMID: 21054931 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Human Mesenchymal Stem Cells from chorionic villi and amniotic fluid are not susceptible to transformation after extensive in vitro expansion. Cell Transplant. 2010 Nov 5; Authors: Poloni A, Maurizi G, Babini L, Serrani F, Berardinelli E, Mancini S, Costantini B, Discepoli G, Leoni P Mesenchymal Stem Cells (MSCs) are promising candidates for cell therapy and tissue engineering. Increasing evidence suggests that MSCs isolated from fetal tissues are more plastic and grow faster than adult MSCs. In this study, we characterized human mesenchymal progenitor cells from chorionic villi (CV) and amniotic fluid (AF) isolated during the first and second trimesters, respectively, and compared them with adult bone marrow-derived MSCs (BM). We evaluated 10 CV, 10 AF and 6 BM samples expanded until the MSCs reached senescence. We used discarded cells from prenatal analyses for all the experiments. To evaluate the replicative stability of these cells, we studied the telomerase activity, hTERT gene transcription and telomere length in these cells. Spontaneous chromosomal alterations were excluded by cytogenetic analysis. We studied the expression of c-myc and p53, tumor-associated genes, at different passage in culture and the capacity of these cells to grow in an anchorage-independent manner by using soft agar assay. We isolated homogeneous populations of spindle-shaped CV, AF and BM cells expressing mesenchymal immunophenotypic markers throughout the period of expansion. CV cells achieved 14±0.9 logs of expansion in 118 days and AF cells achieved 21±0.9 logs in 118 days, while BM cells achieved 11±0.4 logs in 84 days. Despite their high proliferation capacity, fetal MSCs showed no telomerase activity, no hTERT and c-myc transcriptions and maintained long, stable telomeres. A constant expression level of p53 and a normal karyotype were preserved throughout long-term expansion, suggesting the safety of fetal MSCs. In conclusion, our results indicate that fetal MSCs could be an alternative, more accessible resource for cell therapy and regenerative medicine. PMID: 21054927 [PubMed - as supplied by publisher] | | | | | | | | | |  | |  | |  |
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